HOME



picture info

Tentacle (journal)
In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work mainly like muscular hydrostats. Most forms of tentacles are used for grasping and feeding. Many are sensory organs, variously receptive to touch, vision, or to the smell or taste of particular foods or threats. Examples of such tentacles are the eyestalks of various kinds of snails. Some kinds of tentacles have both sensory and manipulatory functions. A tentacle is similar to a cirrus, but a cirrus is an organ that usually lacks the tentacle's strength, size, flexibility, or sensitivity. A nautilus has cirri, but a squid has tentacles. Invertebrates Molluscs Many molluscs have tentacles of one form or another. The most familiar are those of the pulmonate land snails, which usually have two sets of tentacles on the head: when extende ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Cuttlefish
Cuttlefish, or cuttles, are Marine (ocean), marine Mollusca, molluscs of the order (biology), suborder Sepiina. They belong to the class (biology), class Cephalopoda which also includes squid, octopuses, and nautiluses. Cuttlefish have a unique internal mollusc shell, shell, the cuttlebone, which is used for control of buoyancy. Cuttlefish have large, W-shaped pupils, eight Cephalopod arm, arms, and two tentacles furnished with :wikt:denticulate, denticulated suckers, with which they secure their prey. They generally range in size from , with Cephalopod size, the largest species, the giant cuttlefish (''Sepia apama''), reaching in mantle (mollusc), mantle length and over in mass. Cuttlefish eat small molluscs, crabs, shrimp, fish, octopuses, worms, and other cuttlefish. Their predators include dolphins, larger fish (including sharks), seals, seabirds, and other cuttlefish. The typical life expectancy of a cuttlefish is about 1–2 years. Studies are said to indicate cuttlefis ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Pulmonata
Pulmonata or pulmonates is an informal group (previously an order, and before that, a subclass) of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group includes many land and freshwater families, and several marine families. The taxon Pulmonata as traditionally defined was found to be polyphyletic in a molecular study per Jörger ''et al.'', dating from 2010. Pulmonata are known from the Carboniferous period to the present. Pulmonates have a single atrium and kidney, and a concentrated symmetrical nervous system. The mantle cavity is on the right side of the body, and lacks gills, instead being converted into a vascularised lung. Most species have a shell, but no operculum, although the group does also include several shell-less slugs. Pulmonates are hermaphroditic, and some groups possess love darts. Linnean taxonomy The taxonomy of this group according to the taxonomy of the Gastropoda ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Cnidarian
Cnidaria ( ) is a phylum under kingdom Animalia containing over 11,000 species of aquatic invertebrates found both in fresh water, freshwater and marine environments (predominantly the latter), including jellyfish, hydroid (zoology), hydroids, sea anemones, corals and some of the smallest marine parasites. Their distinguishing features are an uncentralized nervous system distributed throughout a gelatinous body and the presence of cnidocytes or cnidoblasts, specialized cells with ejectable flagella used mainly for envenomation and capturing prey. Their bodies consist of mesoglea, a non-living, jelly-like substance, sandwiched between two layers of epithelium that are mostly one cell (biology), cell thick. Cnidarians are also some of the few animals that can reproduce both sexually and asexually. Cnidarians mostly have two basic body forms: swimming medusa (biology), medusae and sessility (motility), sessile polyp (zoology), polyps, both of which are radially symmetrical with mou ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Hole Saw
A hole saw (also styled holesaw), also known as a hole cutter, is a saw blade of annular (ring) shape, whose annular kerf creates a hole in the workpiece without having to cut up the core material. It is used in a drill. Hole saws typically have a pilot drill bit (arbor) at their center to keep the saw teeth from walking. The fact that a hole saw creates the hole without needing to cut up the core often makes it preferable to twist drills or spade drills for relatively large holes (especially those larger than . The same hole can be made faster and using less power. The depth to which a hole saw can cut is limited by the depth of its cup-like shape. Most hole saws have a fairly short aspect ratio of diameter to depth, and they are used to cut through relatively thin workpieces. However, longer aspect ratios are available for applications that warrant them. Common hole saw depths are 38, 45 and 60 mm and for drilling through e.g. (angled-) rooftop constructions also a de ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Crown Cork
The crown cork (also known as a crown seal, crown cap or just a cap), the first form of bottle cap, was invented by William Painter in 1892 in Baltimore. The company making it was originally called the Bottle Seal Company, but it changed its name with the almost immediate success of the crown cork to the ''Crown Cork and Seal Company''. It still informally goes by that name, but is officially Crown Holdings. Overview A Dutch patent application from 1892 This style of closure is still in widespread use. Prior to the invention of the external crown cork bottle stopper, soda bottles had ordinary internal cork bottle stoppers and often had rounded bottoms so they could not be stored standing upright. Corks have a tendency to dry out and shrink, allowing the gas pressure in the bottle to cause the cork to "pop", so bottles were stored on their side to prevent the corks from drying out. After the invention of the crown cork bottle stopper, this problem was eliminated, and soda ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Colossal Squid
The colossal squid (''Mesonychoteuthis hamiltoni'') is a species of very large squid belonging to the family Cranchiidae, that of the cockatoo squids or glass squids. It is sometimes called the Antarctic cranch squid or giant squid (not to be confused with the giant squid in genus ''Architeuthis'') and is believed to be the largest squid species in terms of mass. It is the only recognized member of the genus ''Mesonychoteuthis''. The species is confirmed to reach a mass of at least , though the largest specimens—known only from beaks found in sperm whale stomachs—may perhaps weigh as much as , making it the largest extant invertebrate. Maximum total length is ~. Larger estimates exist, however these include the feeding tentacles measured on dead specimens as in life the squid’s tentacles are hidden, only released when capturing prey. If tentacles are considered, lengths of and exist, but the former estimate is more likely.Roper, C.F.E. & P. Jereb (2010). Family Cr ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Giant Squid
The giant squid (''Architeuthis dux'') is a species of deep-ocean dwelling squid A squid (: squid) is a mollusc with an elongated soft body, large eyes, eight cephalopod limb, arms, and two tentacles in the orders Myopsida, Oegopsida, and Bathyteuthida (though many other molluscs within the broader Neocoleoidea are also ... in the family (biology), family Architeuthidae. It can grow to a tremendous size, offering an example of deep-sea gigantism, abyssal gigantism: recent estimates put the maximum body size at around for females, with males slightly shorter, from the cephalopod fin, posterior fins to the tip of its long cephalopod limb, arms. This makes it longer than the colossal squid at an estimated , but substantially lighter, as it is less robust and its arms make up much of the length. The Mantle (mollusc), mantle of the giant squid is about long (longer for females, shorter for males), and the feeding tentacles of the giant squid, concealed in life, are . Clai ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Umbrella Term
Hypernymy and hyponymy are the wikt:Wiktionary:Semantic relations, semantic relations between a generic term (''hypernym'') and a more specific term (''hyponym''). The hypernym is also called a ''supertype'', ''umbrella term'', or ''blanket term''. The hyponym names a subset, subtype of the hypernym. The semantic field of the hyponym is included within that of the hypernym. For example, "pigeon", "crow", and "hen" are all hyponyms of "bird" and "animal"; "bird" and "animal" are both hypernyms of "pigeon", "crow", and "hen". A core concept of hyponymy is ''type of'', whereas ''instance of'' is differentiable. For example, for the noun "city", a hyponym (naming a type of city) is "capital city" or "capital", whereas "Paris" and "London" are instances of a city, not types of city. Discussion In linguistics, semantics, general semantics, and ontology components, ontologies, hyponymy () shows the relationship between a generic term (hypernym) and a specific instance of it (hyponym ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Peduncle (anatomy)
A peduncle is an elongated stalk of tissue. Sessility is the state of not having a peduncle; a sessile mass or structure lacks a stalk. In medicine, a mass such as a cyst or polyp is said to be ''pedunculated'' if it is supported by a peduncle. There are in total three types of peduncles in the cerebellum of the human brain, known as superior cerebellar peduncle, middle cerebellar peduncle, and inferior cerebellar peduncle. Pedunculated eyes are also the defining attribute of the stylophthalmine trait found in certain fish larvae. The caudal peduncle is a slightly narrowed part of a fish where the caudal fin meets the spine. See also * Peduncle (botany) References Gross pathology {{anatomy-stub ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Ventral Nerve Cord
The ventral nerve cord is a major structure of the invertebrate central nervous system. It is the functional equivalent of the vertebrate spinal cord. The ventral nerve cord coordinates neural signaling from the brain to the body and vice versa, integrating sensory input and locomotor output. Because arthropods have an open circulatory system, decapitated insects can still walk, groom, and mate — illustrating that the circuitry of the ventral nerve cord is sufficient to perform complex motor programs without brain input. Structure The ventral nerve cord runs down the ventral ("belly", as opposed to back) plane of the organism. It is made of nervous tissue and is connected to the brain. Ventral nerve cord neurons are physically organized into neuromeres that process signals for each body segment. Anterior neuromeres control the anterior body segments, such as the forelegs, and more posterior neuromeres control the posterior body segments, such as the hind legs. Neurom ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Cephalopod
A cephalopod is any member of the molluscan Taxonomic rank, class Cephalopoda (Greek language, Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral symmetry, bilateral body symmetry, a prominent head, and a set of cephalopod arm, arms or tentacles (muscular hydrostats) modified from the primitive molluscan foot. Fishers sometimes call cephalopods "inkfish", referring to their common ability to squirt Cephalopod ink, ink. The study of cephalopods is a branch of malacology known as teuthology. Cephalopods became dominant during the Ordovician period, represented by primitive nautiloids. The class now contains two, only distantly related, Extant taxon, extant subclasses: Coleoidea, which includes octopuses, squid, and cuttlefish; and Nautiloidea, represented by ''Nautilus (genus), Nautilus'' and ''Allonautilus''. In the Coleoidea, the molluscan shell has been internalized or is absent, where ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Mantle (mollusc)
The mantle (also known by the Latin language, Latin word pallium meaning mantle, robe or cloak, adjective pallial) is a significant part of the anatomy of molluscs: it is the dorsum (biology), dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself. In many species of molluscs the Epidermis (skin), epidermis of the mantle secretes calcium carbonate and conchiolin, and creates a mollusc shell, shell. In sea slugs there is a progressive loss of the shell and the mantle becomes the dorsal surface of the animal. The words mantle and pallium both originally meant ‘cloak’ or ‘cape’; see mantle (vesture). This anatomical structure in molluscs often resembles a cloak because in many groups the edges of the mantle, usually referred to as the ''mantle margin'', extend far beyond the main part of the body, forming flaps, double-layered structures which have been adapted for many different uses, including for e ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]